outgoing: rework the handling of the `missingroots` case to be faster
The previous implementation was slow, to the point it was taking a significant
amount of `hg bundle --type none-streamv2` call. We rework the code to compute
the same value much faster, making the operation disappear from the `hg bundle
--type none-streamv2` profile. Someone would remark that producing a streamclone
does not requires an `outgoing` object. However that is a matter for another
day. There is other user of `missingroots` (non stream `hg bundle` call for
example), and they will also benefit from this rework.
We implement an old TODO in the process, directly computing the missing and
common attribute as we have most element at hand already.
### benchmark.name = hg.command.bundle
# bin-env-vars.hg.flavor = default
# bin-env-vars.hg.py-re2-module = default
# benchmark.variants.revs = all
# benchmark.variants.type = none-streamv2
## data-env-vars.name = heptapod-public-2024-03-25-zstd-sparse-revlog
before: 7.750458
after: 6.665565 (-14.00%, -1.08)
## data-env-vars.name = mercurial-public-2024-03-22-zstd-sparse-revlog
before: 0.700229
after: 0.496050 (-29.16%, -0.20)
## data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog
before: 346.508952
after: 316.749699 (-8.59%, -29.76)
## data-env-vars.name = pypy-2024-03-22-zstd-sparse-revlog
before: 3.401700
after: 2.915810 (-14.28%, -0.49)
## data-env-vars.name = tryton-public-2024-03-22-zstd-sparse-revlog
before: 1.870798
after: 1.461583 (-21.87%, -0.41)
note: this whole `missingroots` of outgoing has a limited number of callers and
could likely be replace by something simpler (like taking an explicit
"missing_revs" set for example). However this is a wider change and we focus on
a small impact, quick rework that does not change the API for now.
import os
import winreg # pytype: disable=import-error
from typing import (
List,
TYPE_CHECKING,
Tuple,
)
from . import (
encoding,
pycompat,
util,
win32,
)
if TYPE_CHECKING:
from . import ui as uimod
# MS-DOS 'more' is the only pager available by default on Windows.
fallbackpager = b'more'
def systemrcpath() -> List[bytes]:
'''return default os-specific hgrc search path'''
rcpath = []
filename = win32.executablepath()
# Use mercurial.ini found in directory with hg.exe
progrc = os.path.join(os.path.dirname(filename), b'mercurial.ini')
rcpath.append(progrc)
def _processdir(progrcd: bytes) -> None:
if os.path.isdir(progrcd):
for f, kind in sorted(util.listdir(progrcd)):
if f.endswith(b'.rc'):
rcpath.append(os.path.join(progrcd, f))
# Use hgrc.d found in directory with hg.exe
_processdir(os.path.join(os.path.dirname(filename), b'hgrc.d'))
# treat a PROGRAMDATA directory as equivalent to /etc/mercurial
programdata = encoding.environ.get(b'PROGRAMDATA')
if programdata:
programdata = os.path.join(programdata, b'Mercurial')
_processdir(os.path.join(programdata, b'hgrc.d'))
ini = os.path.join(programdata, b'mercurial.ini')
if os.path.isfile(ini):
rcpath.append(ini)
ini = os.path.join(programdata, b'hgrc')
if os.path.isfile(ini):
rcpath.append(ini)
# next look for a system rcpath in the registry
value = util.lookupreg(
# pytype: disable=module-attr
b'SOFTWARE\\Mercurial',
None,
winreg.HKEY_LOCAL_MACHINE
# pytype: enable=module-attr
)
if value and isinstance(value, bytes):
value = util.localpath(value)
for p in value.split(pycompat.ospathsep):
if p.lower().endswith(b'mercurial.ini'):
rcpath.append(p)
else:
_processdir(p)
return rcpath
def userrcpath() -> List[bytes]:
'''return os-specific hgrc search path to the user dir'''
home = _legacy_expanduser(b'~')
path = [os.path.join(home, b'mercurial.ini'), os.path.join(home, b'.hgrc')]
userprofile = encoding.environ.get(b'USERPROFILE')
if userprofile and userprofile != home:
path.append(os.path.join(userprofile, b'mercurial.ini'))
path.append(os.path.join(userprofile, b'.hgrc'))
return path
def _legacy_expanduser(path: bytes) -> bytes:
"""Expand ~ and ~user constructs in the pre 3.8 style"""
# Python 3.8+ changed the expansion of '~' from HOME to USERPROFILE. See
# https://bugs.python.org/issue36264. It also seems to capitalize the drive
# letter, as though it was processed through os.path.realpath().
if not path.startswith(b'~'):
return path
i, n = 1, len(path)
while i < n and path[i] not in b'\\/':
i += 1
if b'HOME' in encoding.environ:
userhome = encoding.environ[b'HOME']
elif b'USERPROFILE' in encoding.environ:
userhome = encoding.environ[b'USERPROFILE']
elif b'HOMEPATH' not in encoding.environ:
return path
else:
try:
drive = encoding.environ[b'HOMEDRIVE']
except KeyError:
drive = b''
userhome = os.path.join(drive, encoding.environ[b'HOMEPATH'])
if i != 1: # ~user
userhome = os.path.join(os.path.dirname(userhome), path[1:i])
return userhome + path[i:]
def termsize(ui: "uimod.ui") -> Tuple[int, int]:
return win32.termsize()